Water → 5,8-Dihydro-2,6,7-trimethyl-1,4-naphthoquinone

HRID 975481

Reaction equation

HRID 975481 reaction equation
[C:1]1([CH3:9])[C:2](=O)[C:3](=[O:7])[CH:4]=[CH:5][CH:6]=1.[CH3:10][C:11]([C:13]([CH3:15])=[CH2:14])=[CH2:12].[OH2:16]>C1(C)C=CC=CC=1.C(O)(=O)C>[CH3:9][C:1]1[C:6](=[O:16])[C:5]2[CH2:12][C:11]([CH3:10])=[C:13]([CH3:15])[CH2:14][C:4]=2[C:3](=[O:7])[CH:2]=1

Participants

6

Reactant 3

HCID 962WaterHCID 105662,3-Dimethyl-1,3-butadieneHCID 123257543-Methylcyclohexa-3,5-diene-1,2-dione

Product 1

HCID 199717765,8-Dihydro-2,6,7-trimethyl-1,4-naphthoquinoneYield 91%

Reagents, catalysts & solvents 2

HCID 176Acetic AcidSolventHCID 1140TolueneSolvent

Procedure

In toluene (30 ml) and acetic acid (10 ml), were dissolved 6.0 g (0,049 mol) of toluquinone, to which 10.0 g (0.12 mol) of 2,3-dimethyl-1,3-butadiene were added at -10° C. under stirring. Thereafter, the resultant mixture was gradually heated and stirred further for 3 hours at 40° C. The liquid reaction mixture was washed with water, and an organic layer was dried and concentrated under reduced pressure. Concentrated hydrochloric acid (1 ml) and ethanol (40 ml) were added to the residue, and the mixture was stirred for 1 hour at 40° C. After the liquid reaction mixture was concentrated under reduced pressure, the residue was dissolved in a liquid mixture of acetonitrile (70 ml) and water (20 ml). To the solution, were added 15.0 g (0.027 mol) of ceric ammonium nitrate at room temperature to stir the resultant mixture for 1 hour. The liquid reaction mixture was poured into water (200 ml) to make extraction with toluene (50 ml×2). The resulting organic layer was washed with water, dried and concentrated under reduced pressure to obtain 8.9 g of a crude product of the title compound (yield: 91%).

Workup

  1. stirringstirred further for 3 hours at 40° C
  2. customThe liquid reaction mixture
  3. washwas washed with water
  4. customan organic layer was dried
  5. concentrationconcentrated under reduced pressure
  6. additionConcentrated hydrochloric acid (1 ml) and ethanol (40 ml) were added to the residue
  7. stirringthe mixture was stirred for 1 hour at 40° C
  8. customAfter the liquid reaction mixture
  9. concentrationwas concentrated under reduced pressure
  10. dissolutionthe residue was dissolved in a liquid mixture of acetonitrile (70 ml) and water (20 ml)
  11. customThe liquid reaction mixture
  12. extractionextraction with toluene (50 ml×2)
  13. washThe resulting organic layer was washed with water
  14. customdried
  15. concentrationconcentrated under reduced pressure

Sources & evidence

ORD record
ord-c93da1179af74843ab0aabd8410ac405
Source dataset
uspto-grants-1997_03
Patent number
US05608092

Linked notes

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